Optical system.



W. VON ROHR,

OPTICAL SYSTEM.

APPLICATION man APR. 30, 19m.

Llsgf@ Patnte June 22, 1915.

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two such IUS ' wisewithoutiniiuence on the fori/notion of interior of this lens there nn eine i nonies vos nenn, on a.

stenen 'ro 'one sinn or conscientes, or

Y PEGAL SYSTEM.

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stationner or tenere :come

Patented June 225, 1 ld5.

spontanen inea .epm to, ieri. lsemi no. esente.

T0 all whom it may concern Re it hewn that l, Morire vor: Renn, e citizen of the German Empire, residing et Jene, Germany, have invented e new and useful Optical System, of which. the follow-- ing is o speciicetion. y

lin the more recent instruments 4for inspeeting cavities in the body severel lens systems of reversion are employed for ob taining o larger entrance upil and thereb en increased luminosity ci the image, :t co lectivo lens systems, which lens is located sp proximotely et the locus of the reel image ying between two adjacent systems of reversion. uch a. collective lens is only intended to servethe purpose of conveying the reysso ,es torender ell the rays, which have entered through the entrance pupil of the instrsnncnt eveileble forv the Pimage preeentegl to the eye, ond is to remain otherthe iniego, the most favorable location for the collective lens 'would be exactly at the locus of the inniget ln this cese, however, any dirt collected on the surface ot' the lens, perticulerly particles of dust, would eppeor magniiied togetherwith the object in the irnsge presented to the observer.

been sometimes used es the collective lens, end this lens hes been so located that in the was the locus of e however, with the which obtain in the reel image. lt is dithcult, small lens dimensions,

. instruments in question, to grind such thick lenses Vwith suiicient accuracy and it was therefore proposed, to form the seid lenses of two ports cemented together. As, however, in using` the above-mentioned instruments, s slight'bending of the containing tube frequently occurs, there 'is always the danger of the cemented joint coming un- 'lhese drawbacks .may be removed according to the invention by dividing the collective lens into two lenses, which are separated by :in aix" space and between which lies the locus of e rcel imageo A simple mode of division and one, therefore, that comes into consideration inthe first place in practice, consists in replacing the collective lens by a, system consisting ci two equal being positioned between eech V consisting also oi two lenses tween the systems ci reversion ln order to avoid this, e comparatively thick lens has ports, which ere positioned 'syen'nietricollyto the imegelocus lying between tliem. When.

at the place v equal to their diameter.

, -he annexed drawing shows diagiemmetically, es on example of how the invcntion muy be applied, the optical system of e cystoscope having two systems of reversion,

system, the

to choose the distance the new collective systems being shown in full lines and the other ports in dotted lines.

ehind e reflecting; prism o there is an objective .consisting of two lenses b1 and b2, which forms in the neighborhood of its lens on imo e of the interior surface of the bladder. his image. is presented by two systems of reversion@ and al to en ocular c1 and c2. Bcf c and al there is s, collective system consisting of two lenses il sind f2, between which there lies the locus oi the reel image and which approximately'replscc e collective lens et the image locus.

il claim: l. @pticel system for s medical appliance adapted to inspect covities in the body, comprising o plurality of systems and u collective systembetween each two such systems of reversion, each such collectivo system consisting of two lenses seperated from one another by an air space, between which lenses lies the locus Aof a reel imager 2. Optical system for o medical epplience adapted to inspect cavities in the body, coinprising o plurality of systems oi' `reversion and eI collective system between cach two s uch systems otreversion, each such collcctive system consisting of two lenses seperated from one another by an air space loeof reversion 

